Paraffin scraper for plunger lift devices



Mar ch 5, 1 935. I. H. BETTIS 1,993,258

PARAFFIN SCRAPER FOR PLUNGER LIFT DEVICES Filed May 16, 1955 I 2o 2/ W T I 1 I l 1 I l l l l LILBE'TTIS INVENTOR ATTORNEY Patented Mar. 5, 1935 UNITED STATE PABAFFIN semen roa mimosa um I DEVICES Irvin H. Bsttis, Oklahoma City, Okla., assignor to Hughes Tool Company, Houston, Tex a cornotation of Texas Application May 10], ms, Serial No. 011,351

I I 5 Claims. My invention relates to plunger lift devices 'where a plunger with a load of liquid may be raised by pneumatic pressure from the bottom to the top of the well. I

My invention is adapted for use particularly where there is paranin or similar material in the cool the paraflln as it approaches the surface and the paramn thus congeals along the upper 1000 or 1500 feet of the tubing.

It is an object of my invention scraper which may be employed with the regular swab plunger and prevent sticking oftheplunger in the tube. I

I desire to provide a device which will fall freely in the fluid in thewell and will act to scrape the paraffin from the tube and allow ittobe discharged from the tube with the oil.

In the drawing Fig. 1 is a central vertical section through one form of my improved scraper. Fig. 2 is a central vertical section through the lower end of the eduction tube with the plunger,

and scraper therein, shown in elevation.

g The eduction tube 1 extends from the surface down into the liquid and has a shoe 2 secured to the lower end by means of the special coupling 3. Said shoe has inlet openings 4 therein at its lower end. I v w I The coupling 3 bass. partition 5, across the same, said partition having openings thereinto allow passage of liquid and gas and also, has a central guide opening for the stem 8 upon the disc '7 which acts as a stop for the 'plunger 8. There is a spring 9 between the disc 7 and-the partition 5 which holds said disc resiliently upward and forms a shock absorber for the plunger. There is also a recoil spring 10 between said partition and the nut 11 on the projecting lower end of the stem 8.

The plunger 8 is of the usual construction. It has an upper cylindrical body fitting somewhat loosely in the tube. The lower end of the body has a valve seat 12 to receive the valve 13. Said valve has a stem 14 which projects downwardly through the support 15. Said support holds the valve in open position when the plunger is falling. By contact of the stem with the disc '7 the valve is forced to the closed position shown in Fig. 2 where the plunger is rising.

My scraper, shown in Fig. 1. has a tubular body 16, the outer surface of which'is cylindrical. The

to provide a 1 inner wall 1'7 converges downwardly to a level near the lower end where it is flared outwardly at 18. At the upperend it has an outwardly extending flange 19 which has a diameter adapting it to fit fairly snugly within the tube. On the inner surface the upper end of the scraper is beveled at 20, thus forming a scraping edge 21. It will be noted that the scraper sleeve is heavy and I contemplate that it shall be about as heavy as the plunger. The body of the scraper moves freely in the tube, and is smaller in diameter than the body of the plunger but the scraping flange 19 is larger in diameter than the plunger and fits the eduction tube as snugly as practical.

In the use of the scraper, it is introduced into the tube above the plunger and may drop simultaneously therewith. On the upwardstroke of the plunger the scraper will engage and remove most of the paramn that has collected. 7 At least, enough of the parailln will be removed to allow the plunger to. drop freely. The scraper may be impeded in its fall by the paraffin, but this will make little difference. for the plunger will engage the scraper on its upward stroke and the gaseous pressure below will be great enough to raise the plunger and scraper and discharge the paraffin with the oil from the tube. The scraping area at 19 is short enough so that there will be little tendency for the scraper to hang up in paraffin on its downward stroke, but where it is slowed'down, the plunger may still fall ahead so that the well will not have time to head up before the plunger reaches bottom. The plunger will, therefore, be enabled to operate continuously in wells which have heretofore had plunger stoppages due to parailin.

ated plunger for raising liquid within an eduction tube in deep wells, a separate scroper above said plunger comprising a sleeve, a flange at the upper end thereof of slightly larger outer diameter than that of the said plunger, said upper end being beveled outwardly to a sharp scraping edge.

2. An eduction tube, a pneumatically operated plunger movable freely therein, in combination with a sleeve above said plunger and movable by sald plunger. said scraper also formed to fit freely in said tube, a short flange on the upper end of said sleeve formed to fit closely in said tube, said flange being beveled outwardly on its inner surface to provide a sharp scraping upperedge.

3. An eduction tube, a pneumatically operated plunger fitting freely in said tube, in combination with a separate scraping sleeve movable by said plunger in said tube and having a scraping edge thereon fitting closely in said tube the outer surface 01' said sleeve below said scraping edge being reduced in diameter to space the same from said tube.

4. An eduction tube, a pneumatically operated plunger fitting freely in said tube, in combination with a scraping sleeve movable in said tube above said plunger and having a scraping edge thereon presented upwardly in said tube, and

fitting closely in said tube, the body of said sleeve below said scraping edge being of smaller external diameter than said edge.

5. In combination with a pneumatically operated, freely moving plunger for use in eduction tubes for wells, a separate scraping sleeve in said tube above said plunger and movable upwardly in said tube by contact of said plunger said plunger being adapted to drop free 0! said sleeve on its downward stroke.

IRVIN H. BE'I'IIS. 

